Islamist cleric Abu Qatada, deported by Britain in July after a near decade-long legal battle, pleaded not guilty as his trial in Jordan on terrorism charges opened Al Jazeera reported.
"You know full well I am not guilty and that this accusation is false," Abu Qatada, in prison overalls, told the judge of the state security court in Amman on Tuesday.
The judge adjourned the case until December 24 after a brief hearing which was open to the media but with cameras banned.
After his deportation, Jordanian military prosecutors charged Abu Qatada with conspiracy to carry out terrorist acts. If convicted he could face a minimum of 15 years' hard labour.
Britain's expulsion of Abu Qatada came after Amman and London ratified a treaty guaranteeing that evidence obtained by torture would not be used in his retrial and that the proceedings would be transparent.
The Palestinian-born preacher was condemned to death in his absence in 1999 for conspiracy to carry out terror attacks, including on the American school in Amman, but this was immediately commuted to life imprisonment with hard labour.
In 2000, he was also sentenced in absentia to 15 years for plotting to attack tourists in Jordan during millennium celebrations.
However, Jordanian law grants him the right to a retrial with him present in the dock.
Born Omar Mahmud Mohammed Othman in Bethlehem in the now occupied West Bank, Abu Qatada has Jordanian nationality because the town was part of Jordan at the time of his birth.
Videotapes of his sermons were allegedly found in the Hamburg flat of 9/11 ringleader Mohammed Atta.
Top Spanish judge Baltasar Garzon once described Abu Qatada as Osama bin Laden's right-hand man in Europe, although he denies ever having met the late al-Qaeda chief.